<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/56345>56345</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Crash by X86 Backend
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:X86,
            crash
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          zhengyang92
      </td>
    </tr>
</table>

<pre>
    https://godbolt.org/z/nof7Eojfo

```
$ cat foo.ll
define <16 x i32> @dec_find_mv_refs(<32 x i16> %a) #0 {
entry:
  %intr1130 = call <16 x i32> @llvm.x86.avx512.pmaddw.d.512(<32 x i16> %a, <32 x i16> %a)
  ret <16 x i32> %intr1130
}

declare <16 x i32> @llvm.x86.avx512.pmaddw.d.512(<32 x i16>, <32 x i16>)

attributes #0 = { "min-legal-vector-width"="0" }




$ /home/liuz/llvm/build/bin/clang -march=cascadelake foo.ll
warning: overriding the module target triple with x86_64-unknown-linux-gnu [-Woverride-module]
SplitVectorResult #0: t7: v16i32 = llvm.x86.avx512.pmaddw.d.512 TargetConstant:i64<10099>, t6, t6

fatal error: error in backend: Do not know how to split the result of this operator!

clang-15: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 15.0.0 (git@github.com:zhengyang92/llvm 84b65ae3a2426201edfe6b6d5a1c27102a152a99)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /home/liuz/llvm/build/bin
clang-15: note: diagnostic msg: Error generating preprocessed source(s) - no preprocessable inputs.
```



@topperc @regehr 
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJyVVU2TozYQ_TX4ooIC8WF88GFnPFu1100qyW2qQQ1oR0iUJGzP_vq0gJ1xdryppMq0aNSoX79-tBsjXo-D95OL8k8R_0y_3ojGKJ8Y25P3nS5tuv2T-daZKD1F6afNVun2W11esBY864xJlFqfCeykRhblj1nFrkzmPMqfWFSkAttn2hLP4_nZYuciXlNQzkNQVi1BvISIH2jNUxbtH9YDUXv7GoAuHgtRkh5lWQjKTwRAqTvplDqPybWuEjhfy4wn0whCXBKRkPOr1I_sPqIfqS36D5ne0Wyc7E-3jFHVCuw9Pv4XwI_Y3mCtFry3spk9uo0-YoYoJIePUscKe1DxGVtvbHyRwg-0QTFkU7rYT6jvWGo1qWIwI9Ki5Bw0EkqgpZmlEmGVmizVq3sWj2DbgTK04FoQqOAF_6GTC1gtdU-NZeaM1kpBHvMDstGIWSHzYHvim8qayLtIPzBi67kq4lm_aHOhoqSer3GvZxaVD_Gf2zEYrwdE5VbSb5OS_o-l9K_oZuUXhkJivw_2nFXUlYWxf-sJ-30B9Gi086A9vSmrIrQ1TQ-HrUW-2uwNcx14UIygGRuyLTdMatZA-4JahGcnw7TxLFTFBrq8YS6AXuiwK2bTkScdMxNaoFIint1mWViPs_ItRbhZW9FZoz1lYq0ZR6C1A6lQrJTildK0RiDbk2h4PTtk8XlBgEgwz4Y-cGn0m9zWM4lqR09ZViZpsrzYS0-iJjvMTUKZKP_3AXX_SuEHvomF1UVTlYA58IJXPM1QdFg1lSgha_k-SzlkJQfi80e6lfRQzK-av8UNFkEE7aAK0ZNx8rpufQkNU1TxSS6s_BcZf-CU-oNhFRJ6bZyXLRvdot6npaE96tCXoOHJ4mRNi84Ryc7MtqVctQuTLaZzbvahUYHjafYuuT9gP9oi9WYiDbRhhljscbBsJ465OOQH2HnpFR4fLbiBNa_sr7piD6vOdrNVPw_992a9kRCWmOB9o--FXOncjAT9c1nlRbkbjnUKZctrgLzdN6Jq8pJ3vOsy0dRpBWW9U9Cgckf6ImmuvGuckISJE8YY523AF9zytJNHntIQ2qcZp_bnddLueVFWBS_g0GBW1lQmjqTYZPk46Q9qZ48LymbuXZij0hF9b5vgnOw14oKAzofZD8Yeb7S4W4o6LhX9DbEpGio">